And it's a -professional- courtesy, whereby you are maintaining a better relationship with the company you're leaving (because you never know if you might some

And it's a -professional- courtesy, whereby you are maintaining a better relationship with the company you're leaving (because you never know if you might some day want/need to come back). The converse, a company letting you go effective immediately, no severance, is sufficiently discourteous that it will likely prevent anyone from -wanting- to come back, as well as will build a reputation for them that will likely prevent a lot of talent from even looking at them as a possibility. It behooves both employees and employers to keep their professional impressions positive.